On January 22nd, President Trump decided to approve the U.S. International Trade Commission’s (ITC) recommendation to impose tariffs on imported solar panels. A new 30% tariff went into effect February 7th and piggybacks the last two tariffs initiated by the Obama administration. The case for imposing more tariffs was launched a few years ago by US solar companies SolarWorld and Suniva which by no coincidence filed for Chapter 11 bankruptcy and insolvency proceedings in 2017. The ITC found that those and other US solar manufacturers have been negatively impacted by solar imports from Asia. Although to a large degree this is true, I also believe US manufacturers need to clean up their own mess. Too many companies for years have been unable to turn a profit from manufacturing solar equipment in the US. Remember the 2011 Solyndra debacle? Striving to make the latest, greatest most efficient solar panel in the world every year comes at a steep price.

Solar panels imported primarily from China and S. Korea will bear the brunt of the new tariffs as those countries account for more than 40% of solar panels that are purchased within the US. The tariffs will start at 30% this year and decrease 5 percentage points per year ultimately terminating in 2022. Utility and commercial scale solar projects will be hit the hardest by the tariff, but I think the residential solar market will feel far less of an impact. Equipment costs on a home project are a lower percentage of the total project cost than say that of a large scale solar farm. However, as a result of the tariff I do anticipate CA residential solar prices to increase an average of $1,100 per home as soon as March 1st.

Of course US based solar manufacturers like Solar World are thrilled. Juergen Stein, CEO of SolarWorld, enthusiastically responded to the tariff, “SolarWorld appreciates the hard work of President Trump and his recognition of the importance of solar manufacturing to America’s economic and national security.”

Economic and national security? That’s funny to me because manufacturing accounts for only 15% of the nearly 300,000 solar jobs in the US. The tariff actually does the rest of us harm. On top of that, Trump has decided to exempt some countries from the tariff. Pakistan for example, which harbors more terrorists than any country in the world, is exempt. How fast did they respond to this news? They’re inviting China-based solar manufacturer Trina to set up shop immediately. ​I do suspect as news of this tariff trickles down that more of my clients will be asking, “Does it make sense now to invest in American Made Solar products for my home?” My answer is “No, unless you feel compelled to buy American and you’re fully aware of the risks.” Historically, choosing domestic brand solar panels over imported ones has cost my clients an average of $2,200 more per project. Hey, we’re proud Americans and I applaud those homeowners that spend a little more to buy ‘Made in America’. Too often though, homeowners are completely unaware of the financial stability of those US made manufacturers they decide to invest in. I’ve always recommended to my clients before their purchase to do a little research on solar equipment companies they are considering like Enphase, SolarWorld, SunPower, and Suniva. In addition, review those solar installers that champion US made brands knowing full well that the equipment they are selling may not be around much longer if it’s from a manufacturer in the red. Here's just one example:

​What happens when what you thought was a 25 year solar equipment warranty is from a brand you invested in that goes belly up? Your solar installer isn’t on the hook, you are! Too many US manufacturers have been unable to furnish even one single quarterly profit to shareholders and it’s not solely a result of lower priced competing imports from Asia.

I suspect the tariff will enable those companies to make some gains temporarily but by no means do I think this is a game changer. Long term, I fear for these US manufacturers and homeowners that willingly invest in them. A 25 year solar panel warranty is worth zero if it’s written on paper printed by a company that’s no longer in business. I hope the Trump tariff serves as a life preserver for a few of those US solar companies without consequences for the rest of us. I fear though the end result will be a temporary boost in the short term for a few companies but overall we’ll realize slower job growth within the US solar sector. SEIA predicts the new tariff could result in 23,000 less solar jobs in 2018. Luckily, at West Coast Solar we’ve secured a large inventory of solar panels ahead of the tariff and our clients won’t be affected by price increases until hopefully April 2018. I do have another question. Will this tariff spark an even broader trade war with China?

​The sun has set on the original net metering program (NEM). The end of 2016 also brought an end to NEM 1.0 and we’re now moving into NEM 2.0 territory. Existing NEM 1.0 homeowners will remain on their original net metering program. Those customers are grandfathered into NEM 1.0 for 20 years from the date of their solar installation. New solar customers will be grandfathered into NEM 2.0 for the next 20 years.

NEM 1.0 was very easy to understand. When your solar is producing more power in kilowatt-hours (kWh) than your home can consume during the day, you deposit those kWh with PG&E. When the sun goes down, you then withdraw as a credit from the grid those excess kWh your solar has produced. Under NEM 1.0 you were able to deposit/withdraw kWh on an even 1:1 basis. That’s now changing a little bit under NEM 2.0. There are 3 major differences to note under the new NEM 2.0 program:​1. Non-bypassable charges (NBC’s)This is a little tricky to explain, but think of it like this: Pretend PG&E is a bank much like Wells Fargo. Let’s say today your home didn’t consume all the solar power it made, so you banked some extra kWh into your savings account with PG&E. A rainy day comes along which is going to reduce your solar production considerably. Thankfully you have some extra kWh saved so you withdraw them from the bank. Under NEM 1.0, PG&E let you make those withdrawals on a 1:1 basis with no surcharge (or ATM fee as we’d call it). The NBC’s are in essence a tiny fee that PG&E is going to charge for every kWh you withdraw from the ATM. I know what you’re thinking, that’s BS. But there’s not much we can do about it. The fee is set at a rate of 2.3 cents per kWh. So how’s that going to look? My average client produces over 10,000 kWh of solar power a year; roughly 50% of those kWh are deposited onto the grid and banked for future withdrawals. The result is that the NBC’s under NEM 2.0 will add about $115 to my average client’s annual true-up bill.

2. One-time solar interconnection feeThere was no NEM application or interconnection fee associated with NEM 1.0. However, PG&E will now get to charge its solar customers a one-time application fee of $145. The new fee can either be paid directly by the homeowner or by the homeowner’s solar contractor. At West Coast Solar, we will be covering the cost of the interconnection fee for our customers.

3. Mandatory adoption of Time-Of-Use (TOU) ratesNo more Tiered rate plans. New solar customers will have to choose from one of three rate plans post solar.

E-TOU-A (peak 3-8pm)

E-TOU-B (peak 4-9pm)

EV (electric vehicle)

I’m recommending my clients go with E-TOU-A. It’s hard yet to predict how the new TOU rates will impact an annual true-up bill, but ideally you want to consume more power during off peak periods and produce more solar power during peak hours. E-TOU-A kWh summer rates from Jun-Sep will be set at $.33/kWh off peak and $.40/kWh on peak. I’m guessing that the placement of solar panels on western facing roofs may prove to be just as valuable as having them face south. The more solar power that can be produced between 3-8pm on E-TOU-A the better. Doing laundry and running swimming pool pumps off peak hours is highly recommended under the NEM 2.0 program.

That’s pretty much it. TOU peak periods are set in stone for the next 5 years. If you have an existing system and plan to expand down the road, be careful. Adding more than 10% power to the solar system you have in place now will force your home to graduate from NEM 1.0 to 2.0.

​Powering your home with solar involves two significant pieces of equipment: Solar Panels which produce electricity in the form of direct current (DC); and an Inverter whichconverts the DC electricity made by the solar panels into alternating current (AC) which is the type of electricity needed to power your home.

There's 3 types of inverter options available to homeowners today: A central inverter which was the only type of proven inverter readily available to the residential market before 2011. A solar breakthrough was realized around that time when Enphasemicroinverters came along and offered so many advantages over traditional central inverters. Then a few years ago, a third option started to make some real noise, and I like to call it a 'hybrid' option as it combines the benefits of both central inverters and microinverters. That option is the SolarEdge power optimizer.

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​So what's the difference between microinverters and power optimizers?

Enphase microinverters (about the size of an iPad) are mounted under each solar panel on the roof and directly converts the solar panel's DC current into AC current. Power Optimizers are similar to microinverters in that they also are mounted under each panel and perform maximum power point tracking, but they do not convert DC electricity into AC on the roof. The SolarEdge power optimizers go a step further, essentially ‘optimizing’ the voltage and current running through the solar panels to harvest the maximum level of power out of each panel and sends that power to a central inverter which does the hard work of converting the optimized DC current into AC electricity.

Both products are similar and offer significant advantages over using a central string inverter:

25 year warranty

Higher efficiency means more power

Design flexibility enabling the use of multiple roof slopes, tilt angles and azimuths

Panel-by-panel monitoring

Both mitigate power loss due to partial shading from trees and obstructions

So which should you choose for your home? Both are great options and I recommend choosing one or the other over using just a central inverter. But I can specifically think of 3 Reasons you should choose Power Optimizers over Microinverters: Reliability. Higher Energy Production. Lower Cost.

1. RELIABILITYOne advantage power optimizers have over microinverters is the issue of HEAT. The DC to AC conversion within a microinverter dissipates heat. We all know the hotter anything gets, the less efficient it becomes. Power optimizers have an advantage over microinverters since the heat generated at the conversion process is done at the central inverter which is usually located inside a garage or outside on a wall near your main electrical panel out of the direct sunlight. The inverter part of your solar is the nuts and bolts component, the ‘moving parts’ of your solar system. Having that moving part of your solar system multiplied for every solar panel on your roof I believe makes your solar system less reliable. Power optimizers need only half the amount of 'moving parts' inside a microinverter. Multiple microinverters tasked with DC to AC conversion year after year and more specifically during summer heat waves I think results in a higher risk of failure. Thankfully both the Enphase and SolarEdge product warranties are quite long at 25 years. A disadvantage with microinverters is their risk of ‘power clipping’. Enphase’s largest sized residential microinverter is its M250 model which refers to its ability to produce a maximum 250w AC output from each solar panel when connected to the microinverter. Unfortunately this limits your choice of brand, type and size of the solar panel you can effectively pair with an Enphase system. Want a 72 cell solar panel? Sorry, not compatible. Choose a solar panel with an output greater than 250w AC, and you run the risk of clipping the top off your solar panel’s production at 250w AC. On the pairing recommendation of Enphase's website it denotes that the M250 can be paired with solar panels with ratings up 310w DC.

​Unfortunately, this is a bit of an overstatement. I’ve installed a handful of solar systems using Enphase M250’s with solar panels sized between 285w- 300w DC that have been negatively been affected by power clipping.So far in my career I've installed slightly more Enphase systems than SolarEdge, and both are exceptional upgrades to the stand alone central inverter. I can count on two hands how many SolarEdge systems I’ve had issues with that involved some form of maintenance or replacement. The majority of those involved replacing the inverter only, and had nothing to do with the power optimizers. That’s why I love the extended 25 year warranty SolarEdge provides for its central inverter to mirror its 25 year power optimizer warranty. On the flip side of that coin I’ve had 3 times the amount of service calls involving Enphase, all of which required troubleshooting the Enphase monitoring system or replacing faulty microinverters. And let me tell you, it’s a lot easier to replace a defective wall mounted central inverter at ground level than it is to replace a microinverter on the roof. Why does it seem that every time a microinverter goes out it happens to be smack dab in the middle of the solar array? It’s never a microinverter on the perimeter, so we have to temporarily lift and set aside 4-6 panels just so we can reach the one panel in the middle with the faulty microinverter. Frustrating!

2. HIGHER ENERGY PRODUCTIONCurrently, the peak efficiency of an Enphase microinverter is 96.5%. The peak efficiency of SolarEdge power optimizers is 99.5%. Remember though, the SolarEdge system is a hybrid that adds the central inverter component. That central inverter operates at 97.6% efficiency. So with a little math we find that a 99.5% peak power optimizer efficiency multiplied by 97.6% central inverter efficiency equals a peak efficiency of 97.1% with SolarEdge compared to 96.5% with Enphase. That may not seem like a big difference at first glance, but it adds up day by day, year over year. Truth be told, there are those that state Enphase may produce a higher energy yield over SolarEdge, but they’ll never back it up with an accurate apples to apples comparison. Here's a side by side case study that proves just how much SolarEdge Power Optimizers will outproduce Enphase Microinverters.When a solar panel is shaded from a tree, chimney or a cloud in the sky during the course of a day, its voltage drops. At night, the voltage drops to zero obviously until the sun comes up the next day. To capture power produced by a solar panel, your system is limited by the minimum voltage required by the inverter. The lower the minimum voltage, the greater the amount of energy that can be harvested. A central inverter usually requires a minimum system voltage over of 125v. An Enphase microinverter requires a minimum voltage of 22v. The SolarEdge power optimizers start tracking at only 5v. This means they’ll produce more power in shaded conditions and kick on earlier in the morning thus producing more power as the sun comes up.

3. LOWER COSTI know it’s hard to believe. “So what you’re telling me Mike is that power optimizers are more reliable and produce more power than microinverters but cost less?” In a word: YES. A microinverter system is comprised of sophisticated monitoring parts, components and AC trunk cabling not required by SolarEdge. However there is no central inverter to install like with the SolarEdge system, true. On the surface, adding a central inverter to the system sounds like it should cost so much more but it doesn’t. A microinverter is about 2 ½ to 3 times the cost of a power optimizer, and remember it has twice the amount of ‘moving parts’. It’s pretty much like taking a central inverter and dividing it up into 24 smaller inverters over an entire solar system. That’s not cheap. Although the SolarEdge solution requires adding the cost of a central inverter, when you add up all of the microinverter equipment, cabling, monitoring, warranties and the labor to install the Enphase system, the upfront cost to a homeowner is still about 10% more than SolarEdge.

So there you have it: Better reliability, more energy produced and a lower cost. When it came down to deciding which upgrade I wanted for my home’s solar system, the choice was easy. I have SolarEdge and you should too.